首页> 外文期刊>The Astrophysical journal >STRONG CLUSTERING OF FAINT GALAXIES AT SMALL ANGULAR SCALES
【24h】

STRONG CLUSTERING OF FAINT GALAXIES AT SMALL ANGULAR SCALES

机译:小角度尺度上星系的强烈聚类

获取原文
获取原文并翻译 | 示例
           

摘要

The two-point angular correlation function of galaxies, ω(θ), has been computed on equatorial fields observed with the Cerro Telolo Inter-American Observatory 4 m prime focus, within a total area of 2.31 deg~2. In the magnitude range 19 ≤ m_R ≤ 21.5, corresponding to < z > ≈ 0.35, we find an excess of power in ω(θ) at scales 2″ ≤ θ ≤ 6″ over what would be expected from an extrapolation of ω(θ) measured at larger θ. The significance of this excess is ≈ 5 σ. At larger scales, 6″ < θ ≤ 24″, the amplitude of ω(θ) is 1.6 times smaller than the standard nonevolutionary model. At these scales there is remarkable agreement between the present data and Infante & Pritchet (1995). At large angular scales (6″ < θ ≤ 24″) the, data are best described by a model where clustering evolution in ξ(r, z) has taken place. Strong luminosity evolution cannot be ruled out with the present data. At smaller scales, 2″ ≤ θ ≤ 6″, our data are formally fitted by models where ε = -2.4(Ω = 0.2, r_0 = 5.1 h~(-1) Mpc) or r_0 = 7.3 h~(-1) Mpc (Ω = 0.2, ε = 0). If the mean redshift of our sample is 0.35, then our data show a clear detection of the scale (≈ 19 h~(-1) kpc) where the clustering evolution approaches a highly nonlinear regime, i.e., ε ≤ 0. The rate at which galaxies merge has been computed. If this rate is proportional to (1 + z)~m, then m = 2.2 ± 0.5.
机译:星系的两点角相关函数ω(θ)是在塞罗泰洛洛美洲国家天文台4 m主焦点上观测到的赤道场上计算得到的,总面积为2.31 deg〜2。在19≤m_R≤21.5的幅度范围内(对应于≈0.35),我们发现在ω(θ)中,比例尺为2“≤θ≤6”时,ω(θ)的功率超出了对ω(θ )在较大的θ处测量过量的重要性为≈5σ。在6“ <θ≤24”的较大范围内,ω(θ)的幅度是标准非进化模型的1.6倍。在这些规模上,目前的数据与Infante&Pritchet(1995)之间有着显着的一致性。在较大的角度比例下(6英寸<θ≤24英寸),最好用一个模型描述数据,其中发生了ξ(r,z)的聚类演化。用目前的数据不能排除强烈的光度演变。在2“≤θ≤6”的小尺度下,我们的数据通过ε= -2.4(Ω= 0.2,r_0 = 5.1 h〜(-1)Mpc)或r_0 = 7.3 h〜(-1)的模型正式拟合。 Mpc(Ω= 0.2,ε= 0)。如果我们的样本的平均红移为0.35,则我们的数据将清楚地检测到规模(≈19 h〜(-1)kpc),其中聚类演化接近高度非线性状态,即ε≤0。已计算出哪些星系合并了。如果该比率与(1 + z)〜m成正比,则m = 2.2±0.5。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号